GB1400438A - Polymerisation process - Google Patents

Abstract

1400438 Continuous olefin polymerization IMPERIAL CHEMICAL INDUSTRIES Ltd 8 Nov 1972 [22 Nov 1971] 54119/71 Heading C3P Copolymers of ethylene and C 3 -C 10 α- olefins, optionally with a non-conjugated diene, are produced by continuously introducing ethylene, a liquid C 2 -C 10 α-olefin, optionally said diene, and a catalyst slurry to a polymerization zone where they are continuously reacted to produce a slurry of copolymer particles suspended in the α-olefin which slurry containing any unreacted ethylene and optional diene is continuously removed from said zone, continuously separating the copolymer particles from the liquid α-olefin, unreacted ethylene and optional diene and recycling the α-olefin to the polymerization zone. The catalyst slurry is a suspension in a liquid inert hydrocarbon of the catalyst claimed in Specification 1,314,828 which is the product of reacting a substantially inert matrix which has surface hydroxyl groups but which is free of adsorbed water and a transition metal complex R m MX p where M is a Group IVA to VIA transition metal, R is a hydrocarbon or substituted hydrocarbon group, X is a singly charged anionic ligand or monodentate neutral ligand, m and p are integers, m having a value from 2 to the highest valency of M and p having a value from 0, to 2 less than the valency of M except when M is a Group VIA metal when p is always 0. The matrix may be silica, alumina or mixtures thereof. The separation may be done using a centrifuge, a thin film contact dryer, a spray dryer or a pressure filter. The Specification lists many suitable non-conjugated dienes including 1,4-hexadiene, 5-ethylidene (or methylene isopropenyl or 1-propenyl) or 2-norbornene, 1,4 - endomethylene - 6 - methylhexahydronaphthalene and dicyclopentadiene. In the examples ethylene and propylene with and without 5-ethylidene-2-norbornene are continuously copolymerized in the presence of hydrogen using as a catalyst a slurry of the reaction product of zirconium tetrakis (trimethylsilylmethylene and alumina in propane.